1. Field of the Invention
The present invention relates to a semiconductor device, for example, a semiconductor device used for an electronic card.
2. Description of the Related Art
In recent years, IC cards and memory cards in which a semiconductor integrated circuit (IC) chip is buried in a card have come into wide use. In the following description, the above IC cards and memory cards, that is, cards in which the IC chip is buried are collectively called as an electronic card.
The electronic card can store large-capacity data as compared with existing magnetic cards and can be more readily downsized as compared with existing magnetic disks. From the above features, the electronic card is one of media having a possibility of being replaced with magnetic cards and magnetic disks in future.
In the field of the electronic card, high function and large capacity are required in addition to the above miniaturization, similarly to the IC chip. For this reason, the component mounting density of the IC chip in the electronic card is rapidly increasing. When the component mounting density becomes high, the distance from the card outer surface to the IC chip becomes narrow. As a result, this is a factor of increasing the possibility that an external surge is directly inputted to the IC chip.
In the electronic card, a human carrying the electronic card has high possibility that he becomes a source of surge. A portion having high possibility that the surge is inputted is a portion where the human unconsciously picks up the electronic card. As depicted in FIG. 25A, adjacent two corners of the electronic card are given as the above unconsciously picked-up portion. For example, two corner portions opposite to the side of the electronic card inserted into the electronic apparatus have attracted special interest.
As illustrated in 25B, the human are easy to unconsciously pick up the above two corner portions when inserting the electronic card into the electronic apparatus or pulling out of there. Such a tendency appears more remarkably when the electronic card is downsized, for example, a width Wcard of the electronic card becomes small.
As described above, when the electronic card is downsized and high-density mountability is improved, the IC chip mounted in the electronic card has high possibility that the surge is directly inputted to there. For this reason, any suitable steps must be taken with respect to not only the electronic card but also IC chips mounted in the electronic card.